U.S. patent number 4,959,671 [Application Number 07/308,085] was granted by the patent office on 1990-09-25 for vertical tilting apparatus of tripod head.
This patent grant is currently assigned to Heiwa Seiki Kogyo Co., Ltd.. Invention is credited to Masao Ishikawa.
United States Patent |
4,959,671 |
Ishikawa |
September 25, 1990 |
Vertical tilting apparatus of tripod head
Abstract
A vertical tilting apparatus of a tripod head for a camera or
the like is disclosed. The vertical tilting apparatus includes a
torque changeover mechanism. The structure of the torque changeover
mechanism comprises a disk-shaped first unit, a second unit, a unit
securing pin and a second unit case on the second unit. The first
unit consists of many first damp adjusting plates and first
intermediate bodies. The second unit consists of ring-shaped
intermediate bodies opposite to the surfaces of the first
intermediate bodies, a viscous fluid therebetween and second damp
adjusting bodies. The first unit and the second unit arranged
concentrically. The unit arc securing pin can be releasably
inserted into any of holes provided on the circumferential surface
of the second unit case for use.
Inventors: |
Ishikawa; Masao (Yashio,
JP) |
Assignee: |
Heiwa Seiki Kogyo Co., Ltd.
(Yashio, JP)
|
Family
ID: |
23192482 |
Appl.
No.: |
07/308,085 |
Filed: |
February 9, 1989 |
Current U.S.
Class: |
396/428;
248/183.2 |
Current CPC
Class: |
F16M
11/10 (20130101); F16M 11/2014 (20130101); F16M
2200/041 (20130101) |
Current International
Class: |
F16M
11/02 (20060101); F16M 11/12 (20060101); F16M
11/10 (20060101); G03B 029/00 () |
Field of
Search: |
;354/81,82,293 ;352/243
;248/177,178,183 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Brown; Brian W.
Attorney, Agent or Firm: Armstrong, Nikaido, Marmelstein,
Kubovcik & Murray
Claims
What is claimed is:
1. A torque changeover mechanism for a vertical tilting apparatus
of a tripod head which incorporates a securing disk that maintains
the horizontal state of a camera mounted thereon in balance with
elastic bodies acting in opposition to each other at right and left
ends of a horizontal shaft in the vertical tilting apparatus, said
torque changeover mechanism comprising:
a first unit incorporating the horizontal shaft and having a
plurality of first damp adjusting plates and first intermediate
bodies wherein the first change adjusting plates and the first
intermediate bodies are concentrically and alternatingly arranged
with each other along the longitudinal axis of the shaft, the first
damp adjusting plates and the first intermediate bodies being
securely fit with the shaft;
a second unit having ring-shaped second intermediate bodies and
second damp adjusting plates wherein the second intermediate bodies
and second damp adjusting plates are concentrically and
alternatingly arranged with each other relative to the longitudinal
axis of the shaft, said first unit being inter-engaged with said
second unit such that each first damp adjusting plate is co-axially
positioned with a corresponding second intermediate body along a
first plane and each first intermediate body is co-axially
positioned with a corresponding second damp adjusting plate along a
second plane;
a unit case for holding and sealing therein said inter-engaged
first and second units, said second unit being securely fit in said
unit case and said unit case having a plurality of securing holes
defined along a radius on a surface of said unit case;
a unit securing pin releasably insertable into any of the securing
holes on said unit case for securing said first and second units to
allow torque balance adjustment; and
viscous fluid filled into said unit case and between said
inter-engaged first and second units.
2. The torque changeover mechanism as claimed in claim 1, wherein
said unit securing pin is provided with a spring for holding said
securing pin in the securing holes and a torque unit changeover
knob attached to said securing pin to allow handling of said
securing pin.
3. The torque changeover mechanism as claimed in claim 1, wherein a
support for the vertical tilting apparatus is provided on a fitting
base of the tripod head for connection to a tripod through a
horizontal swiveling apparatus in the tripod head, and the
horizontal shaft of the first unit is bearing-supported on said
support.
4. The torque changeover mechanism as claimed in claim 1, wherein
the horizontal shaft is bearing-supported on a support cap in the
tripod head through a first unit clamping nut.
Description
FIELD OF THE INVENTION
The present invention relates to a vertical tilting apparatus of a
tripod head for a camera or the like.
DESCRIPTION OF PRIOR ART
The conventionally known vertical tilting apparatuses to be fitted
to a tripod head are defective in that the balance of coil springs
arranged on both sides cannot be altered or adjusted.
Particularly, in an apparatus of the type adapted to a camera
having the center of gravity thereof located in the front portion.
For example the rear portion of the apparatus becomes too low for a
camera having the center of gravity thereof located in the rear
portion. In an apparatus of the type adapted to a camera having the
center of gravity thereof located in the rear portion thereof, the
front portion of the apparatus becomes too low for a camera having
the center of gravity located in the front portion.
To solve this defect in the prior art, a vertical tillting
apparatus of a tripod head has previously been proposed comprising
a horizontal shaft provided on a support arranged through a
horizontal swiveling apparatus on a fitting base to a tripod or the
like; a securing disk for a camera or the like provided across the
top portions of a pair of right and left leg members
bearing-supported rotatably in the forward and back directions; a
pair of right and left coil springs between leg members and a
support having an elastic force stronger than the approximated
weight of a prescribed camera or the like to be mounted on the
securing disk so that the elastic force thereof acts in the
opposite direction to the approximate weight, and that the securing
disk for the camera or the like keeps the horizontal state when the
elastic force of both springs is in balance with said prescribed
camera or the like as mounted. The vertical tilting apparatus
comprises directly or indirectly a plurality of engaging hubs
arranged along a circle around the horizontal shaft as the center
on the support side, and an engaging latch engaging or disengaging
selectively with any of said plurality of engaging hubs through
operation of a knob on the leg member side (Provisional Publication
No. 104,894/86 of Japan Utility Model).
However, this vertical tilting apparatus having excellent functions
still have several points to be improved, such as the necessity of
further simplifying operations and achieving a more satisfactory
torque balance by smoothing vertical tilting movement.
SUMMARY OF THE INVENTION
To solve the above-mentioned problems, an object of the present
invention is to provide a vertical tilting apparatus for a tripod
head which comprises a securing disk for a camera or the like
keeping the horizontal state thereof when the elastic force of
elastic bodies provided the right and left ends of a horizontal
shaft is in balance with a camera or the like in the mounted state.
The vertical tilting apparatus comprises a first unit consisting of
a disk-shaped body of a plurality of first damp adjusting plates
and first intermediate bodies, a second unit consisting of
ring-shaped second intermediate bodies arranged opposite to the
surfaces of the first intermediate bodies, a viscous fluid sealed
therebetween, and a plurality of second damp adjusting plates
arranged between the circumferential surfaces of the second
intermediate bodies; said second unit being arranged concentrically
with said first unit by means of clamping rings fitted on the
horizontal shaft, and a torque changeover mechanism comprising a
unit securing pin releasably engaging with a hole provided on the
circumferential surface of the second unit case.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 and 2 are a perspective view and a longitudinal sectional
view illustrating a conventional vertical tilting apparatus of a
tripod head as in the prior art related to the present invention;
and
FIGS. 3 and 4 are a partial longitudinal sectional view and a
partial perspective view illustrating an embodiment of the torque
changeover mechanism of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention therefore provides an improvement over a
previously proposed vertical tilting apparatus. The present
invention is described in detail below with reference to the
drawings.
In the previously proposed vertical tilting apparatus, as shown in
FIGS. 1 and 2 for example, a pan ring (2) is unrotatably fitted to
the lower surface portion of a horizontal rotating body (1), and a
pan adjuster (3) is rotatably engaged into the inner bore of the
pan ring (2). A first oil ring bearing unit (9) comprising a
doughnut-shaped fitting strip (4), an o-ring made of an
oil-resistant rubber (5), an oil shield ring (6), a member for
forming shaft hole (7) and a clamp screw (8) is unrotatably fitted
to the upper surface of the pan adjuster (3).
A downward center shaft (10) is provided in projection, and
rotatably inserted into the shaft hole of the first oil ring
bearing unit (9) so that the leading end of the center shaft (10)
projects from the lower surface of the pan adjuster (3). A pair of
ball bearings (11) are engaged with the uppermost and the lowermost
positions of the projection. A hollow hemispheric base (12) is
secured by means of a screw (13) to the lower surface of the pan
adjuster (3). The horizontal rotating body (1) is horizontally
rotatably bearing-connected onto the base (12) with the lower
surface thereof as a spherical journal.
Full stoppage and full release of horizontal rotation of the
horizontal rotating body (1) can be accomplished through tightening
and loosening of a screw stock (14). The function of providing
semi-damping of a prescribed intensity can be performed for the
horizontal rotation of the horizontal rotating body (1) through
tightening and releasing of a screw stock (15).
A horizontal shaft is unrotatably inserted into a horizontal hole
(21) pierced through an upward support (20) on the upper surface of
the above-mentioned horizontal rotating body (1). A pair of
T-shaped leg members (23) are arranged on both sides of the support
(20). Bearing holes are provided in the lower end portions of these
leg members (23), which are engaged rotatably to the horizontal
shaft (22) in the forward and back directions.
A securing disk (25) for camera or the like is provided across the
space between horizontal members (24) by means of screws. A second
oil ring bearing unit (26) having the same structure as the
above-mentioned first oil ring bearing unit (9) is unrotatably
engaged around the leading end of the horizontal shaft (22) both on
the inner and on the outer sides of each of a right and a left leg
members (23). By attaching it to a ball bearing (27), an arresting
plate (28) and a set screw (29), it supports the leg members (23)
movably in the forward and back directions. A doughnut-shaped space
is formed by cutting grooves (30) opening one opposite to another
on the desired positions of a circle with the above-mentioned
horizontal shaft (22) as the center on the inner sides of the right
and left leg members (23) and on the both sides of the support
(20). A pair of tilt adjusting rings (31) having washer-like play
strips contacted with both their sides is inserted into this space.
For one of the tilt adjusting rings (31), a tilt securing screw
(32) with a knob engages with and disengages from a screw hole
pierced in one of the leg members (23) to conduct and release
pressure contact.
A recess (33) opening is horizontally cut around the horizontal
shaft (22) the both sides of the support (20). A pair of right and
left coil springs (34) having an elastic force stronger than the
approximate weight of the camera or the like to be mounted on the
above-mentioned securing disk (25) are wound around the horizontal
shaft (22) in the recess (33) so that the elastic force acts in the
opposite direction each other. The inner ends of these coil springs
(34) are engaged with engaging holes (35) pierced in the bottom
surface of the recess (33), and the outer ends thereof are engaged
with engaging holes (36) pierced in the inner surface of the leg
members (23). The positions of these engaging holes (35) and (36)
are such that the securing disk (25) not mounting a camera or the
like keeps the horizontal state by the balance of elastic force of
the respective coil springs (34).
Covering bodies (37) are arranged outside the above-mentioned
arresting plate (28), and the outer circumferences of these
covering bodies (37) are secured to the leg members (23) by means
of screws (38). A through-hole is provided on the outer
circumference of one of the covering bodies (37), through which a
pin (39) is slidably inserted. A flange is provided at a position
near the inner end of this pin (39) to prevent the pin from coming
off. An operating knob (40) is unrotatbly fixed to the outer end of
the pin (39) by means of a screw. A cam unit is provided, which
causes the pin (39) to move inside and to outside under the effect
of a spring (41).
A plurality of recesses (42) are provided at prescribed intervals
along a circle containing points corresponding to the inner end of
the pin (39) on the outer side of the second oil ring bearing unit
(26) so that the inner end of the above-mentioned pin (39) is
selectively engaged with and disengaged from one of these recesses
(42) by positively or negatively turning the operating knob
(40).
The invention covered by the present application provides a further
improvement over the vertical tilting apparatus of a tripod head
having the detailed structure as described above, for the purpose
of achieving easier operation and permitting proper adjustment of
the torque balance. The improvement proposed by the present
invention relates to the second oil ring bearing unit (26) of the
above-mentioned structure comprising the provision of a torque
changeover mechanism of the following structure for the horizontal
shaft (22).
The improvement is characterized by the torque changeover mechanism
in which a first unit comprising a disk-shaped plate body
consisting of a plurality of first damp adjusting plates and first
intermediate bodies and a second unit comprising ring-shaped second
intermediate bodies opposite the surface of the first intermediate
bodies, a viscous fluid sealed in between, and second damp
adjusting plates provided between the circumferential surfaces of
the second intermediate bodies. The first and second units are
arranged concentrically on the horizontal shaft by means of
clamping rings, and a unit securing pin is releasably inserted into
a hole provided on the circumferential surface of the second unit
case.
Typical features of this torque changeover mechanism is illustrated
in FIG. 3.
In the torque changeover mechanism, as shown in FIG. 3, the first
unit comprises a disk-shaped plate body consiting of the first damp
adjusting plates (103) and the first intermediate bodies (104)
clamped to the horizontal shaft (100) of a tripod head by means of
a clamping ring (101) and a clamping nut (102).
The respective first intermediate bodies (104) have diameters
larger than that of the clamping ring (101) and the circumferential
surfaces thereof reach even the interior of the second unit
separated from the above-mentioned first unit. More specifically,
the second unit comprises the ring-shaped second intermediate
bodies (105) opposite to the surfaces of the first intermediate
bodies (104), the viscous fluid (106), such as viscous grease,
sealed in between, and the second damp adjusting plates (107)
provided on the circumferential surfaces of the second intermediate
bodies (105) arranged concentrically with the first unit. The
second damp adjusting plates (107) and the second intermediate
bodies (105) are housed in a second unit case (109) by clamping
them between the second unit case (109) and a second unit cap (110)
by means of clamp screws (108).
The second unit is tiltable in the forward and back directions
relative to the first unit. Adjustment of torque balance in this
case is accomplished by selecting any of a plurality of holes (111)
provided on the circumferential surface of the second unit case
(109) and inserting a securing pin (112) in a desired hole (111).
This securing pin (112) is releasably inserted into a hole (111) by
means of a switching knob (114) via spring (113).
The relationship between this hole (111) and the securing pin (112)
is illustrated in FIG. 4.
In the embodiment with the structure as described above of the
present invention, torque adjustment of vertical tilting of the
tripod head is accomplished through shear tilting balance between
the first intermediate bodies (104) and the second intermediate
bodies (105) in the second unit containing the viscous fluid (106)
sealed therein.
Under the effect of this mechanism, vertical tilting in the forward
and back directions of a camera or the like on the tripod head can
have an excellent torque balance.
It is needless to mention that a horizontal swiveling mechanism or
the like may be combined with the present invention as in the prior
art, and various manners may be adopted for the other individual
mechanisms.
* * * * *